تحليل زماني و مكاني دماي سطحي آب درياي خزر با استفاده از توابع متعامد تجربي

The Time and Place Analysis of the Surface Temperature of the Caspian Sea Water With the Use of Empirical Orthogonal Function

Temperature is a fundamental quantity in the physical ocean logy and the basis of study of oenologist in the study and recognition of the processes in oceans and water basins. The time and place changes of the surface temperature of water strata have an important role in the activities of climatic change, the life of aquatic animals, marine processes, saltiness degree and other characteristics at lake and sea water. The aim of this research is the recognition of the manner of the Caspian Sea surface temperature distribution and the factors affecting it. For this purpose water surface data have been investigated for a period of four years with the use of the method of time and place analysis. In the performed analysis, monthly average data for 1400 stations in a period of four years have been used. And the quantities of EOF and PC and period grams and place correlation coefficients for the main modes have been calculated with the use of Empirical Orthogonal Function analysis. Final, seven main modes have been inferred and EOF and PC and their preiodograms were analyses and the factor of each of them was identified. They are as follows with regard to their importance: The first mode due to the radiation of the sun has 98.3 percent in the water surface temperature. The second mode has 1.46 percent that is related to the effect of the deep pit located in the southern Caspian Sea on the Caspian Sea surface temperature. The third mode has 0.094 percent related to the effect of the deep pit located in the medial Caspian. The fourth mode has 0.0265 percent related to the effect of the deep pit located in the north Caspian. The fifth mode has 0.0225 percent related to the effect of the entrance of the water of the Volga River from the side of western north to the Caspian Sea. The sixth mode has 0.0162 percent due to the effect of the temperature of conviction between the sea and the land. And the seventh mode has 0.0102 percent due to the effect of the west winds on the Caspian Sea surface temperature.